The concept of using extremely high frequency of about 60 GHz has been proposed and some of the characteristics thereof have been investigated as described in "Cordless Communication within Buildings: results of measurements at 900 MHz and 60 GHz" by Alexander and Pugliese, Br Telecom Technol J, Vol 1, July 1983, pages 99 to 105. This paper describes a proposed system for using extremely high frequency radio transmission within a building and examines the fading characteristics when employing a particular type of omni-directional aerial modeled on the design of Uenakada et al, "Horizontally polarized biconical horn antenna and metal plate lens," Electronics and Communications in Japan, 59-B, No 7, pp 80 (1976). In this system the energy is coupled to the antenna in a circular wave guide carrying in the TE.sub.01 mode. The resulting radiation is "horizontally" polarized.
In the arrangement used by Alexander et al the central and the subscriber or work station antennae are essentially the same. The concept is to totally flood the whole work space and to use these antennae structures to transmit and receive data between the central or main computer and each of the work or subscriber stations.
It has also been suggested to combine spread spectrum techniques with the use of radio frequency for intraoffice communication, see Pahlavana "Wireless communication for office information networks" IEEE Communications Magazine, Vol 23, June 1985.